1. Field of the Invention
This invention relates to an immobilized enzyme column useful for automatic chemical analyzers by which substances contained in the blood serum, urine or the like are analyzed in combination with an enzyme for clinical tests.
2. Description of the Prior Art
An immobilized enzyme column has a sample supply tube connected to its rear end and a sample discharge tube connected to its front end. Each of the tubes is divided, at a position close to the column, into two segments which are connected together by a three-way joint at two socket portions thereof. An air bubble removing tube is joined to the remaining one socket portion of the joint on the sample supply tube, and an air bubble supplying tube is joined to the remaining one socket portion of the joint on the sample discharge tube. Connected to a rear portion of the sample supply tube is an air supply tube for intermittently supplying air to divide a sample with air bubbles. When different samples are supplied to the column, a preceding sample will mingle with the following different sample, giving an inaccurate value on analysis. To avoid this, the sample is divided by air bubbles. In practice, however, it is difficult to interpose an air bubble accurately between the preceding sample and the following sample. Further if the sample passes through an immobilized enzyme with an air bubble incorporated in the sample, the bubble will diffuse through the sample, adversely affecting the analyzed value, so that there is the need to remove the bubble from the sample before the inlet to the portion of the column where the enzyme is accommodated and to supply an air bubble again to the sample after it has passed through the enzyme. Removal of the bubble nevertheless permits the preceding sample to mingle with the following sample and makes it meaningless to introduce the bubble into the sample. To eliminate such a problem, air is supplied to the same sample so that some dividing air bubbles will be present therein at specified spacing. While the immobilized enzyme accommodating portion in the column is spaced from the bubble removing tube and from the bubble supplying tube, the shorter the spacings, the better, because the longer the spacings, the longer will be the sections in which the preceding sample becomes mixed with the following one and the lesser will be the sample portion to be analyzed reliably. To compensate for this, there is the need to use an increased amount of sample which takes a longer period of time for analysis.